Oauth

Allows an application to access specific resources on behalf of a user

https://knpuniversity.com/screencast/oauth/intro#play

OAuth Actors

OAuth Provider

Based on 3 components

Authentication Provider

Username and Password

Consent Server

Which parts of system a client can access

Token Management Infrastructure

it keeps data like : Access token, refresh token, when it was created and when it's invalid, when it's revoked

Resource Provider

Makes a protected resource available via HTTP Protocol

ie : Twitter

Resource Server

• Holds Resources
• Protects resources
• Makes resources available via API

Resource Owner

Owner of the protected resource.

• Owns resources
• Delegates right to access the resource to a third party app

ie : @aliiybar

Client

An application trying to access a protedted resource.

• Wants to access resources
• Gets and holds Access Token and Refresh Token
• Should NOT hold password of Resource Owner
• Identified via ClientID and Client Secret

ie : Mobile app

OAuth Server - Endpoints

/authorize GET

Input Query Parameters

• state
• scope
• response_type
• client_id
• redirect_uri

Output

according to response_type the output is one of the items below

• Authorization Code (for Authorization Code Grant)
• Access Token (for Implicit Grant)

/token POST

Authorization : Basic clientId:clientSecret

Input Query Parameters

• grant_type
• code
• client_id
• redirect_uri

Output

• Access Token and Refresh Token (for)
  • Authorization Code Grant,
  • Client Credentials Grant and
  • Resource Owner Password Credentials Grant

/verify - not standardized

only internally accessible by Resource Server

Client - Redirect Endpoints

Redirect URI (GET)

Input Query Parameter

• state
• scopes
• code

Resource Server - Resource Endpoint

/api Authorisation : Bearer {Access Token}

Access Token and Refresh Token (for Authorization Code Grant, Client Credentials Grant and Resource Owner Password Credentials Grant)

Tokens

• Access Token
• Refresh Token (it's only for getting a new Access Token, cannot be used to access resources)
• Authorisation Code it's valid for just few minutes. It's for getting Access Token. It can only be processed by OAuth Server it will never be sent to resource provider

Credentials

• Resource Owner Credentials
• Client Credentials : ClientID & ClientSecret
• Access Token
• Refresh Token
• Authorisation Code

Client Registration

• With OAuth Provider
• Client porvides to OAuth Provider
  • Redirect URI
  • Required Scopes
• Client obtains from OAuth Provider
  • ClientID
  • ClientSecret

OAuth Flow

Udemy Lesson

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